Weird implication you made there. I could agree that military might is not created with compulsory nor voluntary military service, it's more like innovation, technological progress and capitalism are necessary in order to increase advancement of army. But you need soldiers in the time of war, you need a lot of them. Someone must operate advanced weaponry on the battlefront.

Btw, US had compulsory conscription under war circumstances before WW2 and for a long time after. Without compulsory conscription there would be problems with defeating Third Reich, because no Soviet Union, nor Allied Powers wouldn't be capable of forcing them out without enough men power.

Compulsory military service in the times of war is normal in every capitalist country, not even mentioning collectivist states like China where it's normal everyday, or half collectivist state like Israel.